10x speed, 10x savings: Constant Contact’s journey from Pinot to ClickHouse

Constant Contact, a well-known name in email and digital marketing for small and mid-sized businesses, undertook a significant overhaul of its real-time analytics stack due to increasing demands for real-time event processing and advanced reporting capabilities. Initially using Apache Pinot, the company faced challenges with data volume management and maintenance, leading to the decision to transition to ClickHouse in 2024. This transition resulted in substantial performance improvements and cost savings, with ClickHouse offering faster query response times and more efficient data handling due to its use of preads and a log-structured merge tree architecture. Software engineer Abhijeet Kushe highlighted the benefits of ClickHouse, including its ease of setup, efficient data migration, and lower infrastructure requirements compared to Pinot. The migration not only enhanced Constant Contact's technical capabilities but also allowed the team to focus more on developing new features rather than on system maintenance, ultimately strengthening the company's position in the competitive digital marketing landscape.